const Shexian = require("../Shexian").Shexian;
const Point = require("../Shexian").Point;

let p1 = new Point(0,0);
let p2 = new Point(-1,1);
let l2 = p1.SquareDistanceTo(p2);
// debugger
// 
let sx1 = new Shexian(p1,p2);
let sx2 = new Shexian(p1,new Point(0,1));
let cos = sx1.angleTo(sx2);